Arnica grows in the meadows and mountains of Europe and North America. The flowers of the plant are most often used as medicine.

Arnica is often found in skin ointments and oils for inflammation and pain relief. It has been used on unbroken skin for aches, bruises, and sprains. Highly diluted preparations of arnica are considered safe for treating injuries. However, full doses of arnica may be toxic when taken by mouth. Arnica may also cause high blood pressure.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

GRADE *

Early study suggests that arnica may lack effect on bleeding time and platelet count. More research is needed to make firm conclusions on the effect of arnica on clotting.

C

Arnica is widely used to prevent or treat bleeding, broken blood vessels, bruising, and swelling. Arnica has been studied for bruises, pain, and swelling. However, there is little evidence to support the use of arnica. Further research is needed to make firm conclusions.

C

Arnica has been used to help slow the progression of diabetic retinopathy. Although the early results are promising, more research is needed in this area.

C

Arnica has not been well studied for its effects on diarrhea. Early research suggests that arnica may decrease the duration of diarrhea in children. Further study is needed.

C

BRN-01, a combination treatment containing arnica, may reduce hot flashes in women undergoing menopause and may serve as a non-hormonal treatment. Further information is needed on the effects of arnica alone before conclusions can be made.

C

Ileus after surgery may include symptoms such as stomach pain, nausea, vomiting, reduced appetite, and problems passing gas or stool. There is early evidence that arnica may reduce the duration of ileus after surgery. More research is needed to make a strong conclusion.

C

Arnica, in combination with Bryonia alba, has been used in people undergoing heart surgery, with a lack of effect. Further research is needed on the effects of arnica alone before firm conclusions can be made.

C

Arnica gel has been applied to the skin for osteoarthritis pain and stiffness. However, more research needs to be done in this area before a firm conclusion can be made.

C

Arnica has been used alone and in combination with other therapies, such as St. John's wort, for pain after surgery. Although some studies report possible benefits, further study is needed before firm conclusions can be made.

C

Arnica has been studied for stroke recovery, with inconclusive results. Currently, there is no clear evidence that arnica is or is not effective in the treatment of stroke.

C

Arnica has been studied for trauma and pain after surgery. Although some benefits have been found, further study is needed to make firm conclusions on the use of arnica for this purpose.

C

Arnica has been studied for relieving pain due to muscle soreness caused by exercise. However, most research suggests negative results. Further study is needed.

D

* Key to grades

A: Strong scientific evidence for this useB: Good scientific evidence for this useC: Unclear scientific evidence for this useD: Fair scientific evidence for this use (it may not work)F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory
The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

For bruising after surgery, three tablets of arnica have been taken by mouth daily for seven days before surgery and 14 days after surgery. Three arnica granules have been placed under the tongue four times daily for one week before surgery and one week after surgery. Arnica has been taken by mouth in the form of SinEcchTM, 1-M capsules, 12-C capsules, three times daily for 3-4 days or on the day of the operation. Two arnica capsules have been taken by mouth 2-6 hours before surgery, followed by four times daily for five days after surgery. Five globules of Arnica D12 have been taken by mouth the night before surgery, two hours before surgery, and then hourly for the remainder of the day after surgery, followed by five globules of Arnica D12 three times daily for up to two weeks after surgery.

For clotting, arnica has been taken by mouth in intervals of 15 minutes, with a lack of effect.

For diabetic eye disease, three pearls of arnica have been taken by mouth three times daily for up to six months.

For bleeding prevention, one tablet of arnica has been placed under the tongue before and after surgery.

For muscle soreness caused by exercise, 1-5 tablets of arnica has been taken by mouth 2-3 times a day, beginning 24 hours before exercise; during the evening before exercise; during the morning and evening on the day of exercise; for three day; or four hours after exercise, with two more tablets taken the following day. One arnica pellet has been placed under the tongue before and after exercise, then twice more on the day of exercise, followed by three times the next day. Five globules of arnica D4 have been taken by mouth three times on the day before exercise, with a lack of effect.

For pain after surgery, two tablets of arnica have been taken by mouth six times on the first day after surgery, then two tablets twice a day for the next seven days. Two doses of arnica have been taken 24 hours before surgery, followed by three doses daily for five days. Three tablets of arnica (D6 or D30 potency) have been placed under the tongue every four hours for two days, followed by three times daily for three days. Three tablets of arnica have been taken by mouth three times daily for two weeks, plus 5 percent arnica ointment applied to the skin three times daily for two weeks, or every 15 minutes for three hours after surgery, then three tablets hourly until bedtime, followed by three tablets the next morning and then three tablets three hours later. Ten pillules of arnica D4 have been taken by mouth three times daily for four days after surgery.

For stroke, one tablet of arnica 30C has been placed under the tongue every two hours for six doses. One packet of arnica powder has been taken by mouth every two hours for six doses.

Arnica tinctures diluted with water and ointments containing 20-25 percent tincture have been applied to the skin 2-3 times a day.

For bruising, 0.25 grams of 20 percent arnica ointment have been applied to the skin twice daily and then covered with a dressing for two weeks.

For muscle soreness caused by exercise, arnica ointment has been applied to the skin. An arnica cream has been applied to the skin at 24 and 48 hours after exercise and left in place for one hour, with a lack of effect. Ten grams of gel containing 5 percent of arnica extract has been applied to the skin twice daily for 15 days.

For osteoarthritis, fresh plant gel has been applied to the skin twice daily for up to three weeks. A dose of 50-100 grams of A. Vogel Arnica Gel® has been applied to the joints three times daily for three weeks.

For pain after surgery, a 5 percent arnica ointment has been applied to the skin three times daily for two weeks, plus three tablets of D6 arnica taken by mouth three times daily for two weeks.

Children (under 18 years old)

There is no proven safe or effective dose for arnica in children.

Safety
The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Avoid in people with known allergy or sensitivity to arnica, or to any member of the Asteraceae or Compositae family (Achillea millefolium, Ambrosia species, Anthemis cotula asters, calendula, chamomile, chrysanthemum, dahlia, daisy, dandelion, dog fennel chicory, Matricaria chamomilla, mugwort, marigold, May weed, sunflower, tansy, and yarrow).

Side Effects and Warnings

Arnica is likely safe when taken by mouth or placed under the tongue short-term.

Avoid in people with known allergy or sensitivity to arnica, or to any member of the Asteraceae or Compositae family (Achillea millefolium, Ambrosia species, Anthemis cotula asters, calendula, chamomile, chrysanthemum, dahlia, daisy, dandelion, dog fennel chicory, Matricaria chamomilla, mugwort, marigold, May weed, sunflower, tansy, and yarrow).

Avoid in pregnant women and in children, due to a lack of evidence.

Pregnancy and Breastfeeding

There is a lack of scientific evidence on the use of arnica during pregnancy or breastfeeding. Avoid in pregnant women and in children, due to a lack of evidence.

Arnica may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants ("blood thinners") such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).

Arnica may increase blood pressure. Caution is advised in people taking drugs that lower blood pressure.

Arnica may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba, and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases.

Arnica may increase blood pressure. Caution is advised in people taking herbs or supplements that lower blood pressure.

Arnica may also interact with Bellis perennis, herbs and supplements for the nervous system, herbs and supplements for the skin, herbs and supplements for the stomach and intestines, herbs and supplements that cause abortion, herbs and supplements that treat abnormal heart rhythms, antidepressants, anti-inflammatory herbs and supplements, cholesterol-lowering herbs and supplements, pain relievers (including anesthetics), and stimulant herbs and supplements.

The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.